#include "prize.h"
#include "bits/stdc++.h"
#define rep(i, n) for(ll i = 0; i < ll(n); i++)
#define rep2(i, s, n) for(ll i = ll(s); i < ll(n); i++)
#define rrep(i, n) for(ll i = ll(n)-1; i >= 0; i--)
#define pb push_back
#define eb emplace_back
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
using namespace std;
using ll = long long;
using P = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vp = vector<P>;
using vvp = vector<vp>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vs = vector<string>;
const int inf = 1001001001;
const ll linf = 1001001001001001001;
template<class T>
bool chmin(T &a, T b) {
if (a > b) {
a = b;
return true;
}
return false;
}
template<class T>
bool chmax(T &a, T b) {
if (a < b) {
a = b;
return true;
}
return false;
}
int find_best(int n) {
auto f = [&](int i) -> bool {
vi v = ask(i);
return v[1] == 0;
};
int ok = n, ng = 0;
while (ok - ng > 1) {
int mid = (ok + ng) / 2;
(f(mid) ? ok : ng) = mid;
}
return ng;
}
